1. Field of the Invention
The invention relates to a power supply circuit cut-off device capable of opening and closing a power supply circuit and to a method of controlling power supply.
2. Description of the Related Art
Japanese Unexamined Patent Publication No. 2011-90902 a power supply circuit cut-off device called a service plug. The power supply circuit cut-off device includes a housing with which a lever is rotatably assembled and a cover is fit to the housing. The cover and the housing are connected and separated by rotating the lever. A power supply terminal connected to the power supply circuit is provided in the housing and closes the power supply circuit. A relay capable of energizing and cutting off the power supply circuit is mounted in the power supply circuit. The relay sets the power supply circuit in an energizable state when a detection terminal mounted in the housing is set in an ON-state and cuts off the power supply circuit when the detection terminal is set in an OFF-state.
A switching operation by the relay takes a certain time and there is a slight lag between a timing when detection terminal is set in the OFF-state and a timing at which the power supply circuit is actually cut off. Accordingly, if the lever is rotated quickly, the power supply circuit is opened before being cut off and there is a possibility of a spark.
The present invention was completed in view of the above situation and an object thereof is to prevent generation of a spark in a separating process of separating a cover.